The National Telecommunications Information Administration (NTIA) is the executive branch's advisory agency on telecommunications issues. In the early 1980s, this agency proposed a plan to raise awareness of a single emergency telephone number to the general public. From that program, the National Emergency Number Association (NENA), a non-profit organization, was created. NENA has since become a leading organization to improving technology and developing guidelines for 9-1-1 (“911”) telephone calls (i.e., emergency telephone calls) to improve response by emergency rescue teams.
Telecommunications has been changing rapidly over the past several years, primarily since the development and growth of the mobile telephone industry and the Internet. New forms of telecommunications have been developing as well. Traditional telecommunications were performed over the public switch telephone network (PSTN). A system to maintain location of subscribers of telecommunications companies operating on the PSTN was developed. Determining the location of subscribers of the telecommunications companies was relatively easy as the locations of telephones were known by the telecommunications companies or carriers due to installing the telephones, establishing billing, or otherwise. However, with the new forms of telecommunications, subscribers are able to use wireless devices that may access different wireless access points to communicate over a communications network such as the Internet. One common interface for wireless access to a communications network includes an IEEE 802.11 communications protocol, which is commonly known by the brand name WiFi. Wireless devices are being configured to have WiFi communications protocols to enable a subscriber to access WiFi enabled access points. Many WiFi enabled wireless devices have global positioning system (GPS) capabilities that are able to communicate GPS location information (i.e., latitude and longitude coordinates) of the WiFi enabled device. While GPS location information may be helpful to track or locate a person at a precise geographical location, such information is not extremely useful in an emergency situation where emergency rescue teams, such as firemen and police, better understand address information for performing an emergency rescue in an emergency situation.
A public safety answering position (PSAP) is used by emergency services to answer calls from the public to notify emergency personnel, such as police or firemen, to respond to an emergency situation. Traditionally, a caller would contact a PSAP and provide location information during the telephone call. When caller identification (i.e., caller ID) was introduced, PSAPs were installed with telephone systems compatible with caller ID to identify names and phone numbers of individuals placing emergency 911 calls. This first version of caller ID is known as type I caller ID. Type I caller ID operates in a single data message format (SDMF) as well as multiple data message format (MDMF) that provide a caller's telephone number, date and time of the call during the ringing interval.
A second type of caller ID or type II caller ID was later developed to communicate name and address information of a second calling party to a called party when a call between a called party and a first calling party is in progress. Type II caller ID uses a multiple data message format (MDMF) that communicates a caller's name, telephone number, date and time. Enhanced 911 is a North American Telephone Network (NATN) feature of the 911-emergency-calling system that uses a reverse telephone directory provided by cellular telephone companies to determine location information of a caller.
There are two types of E911 systems that operate within the United States, Phase I and Phase II. E911 Phase I systems are required to provide an operator with the telephone number, originator, and location of the cell site or base station receiving a 911 call. E911 Phase II systems are required to use an automatic location identification (ALI). However, only 18% of all PSAPs are configured with E911 Phase II systems. The remaining 82% of PSAPs are configured with E911 Phase I systems, which are incapable of handling GPS coordinates, and, therefore, subscribers who have wireless telephones that use GPS coordinates for 911 emergency calls cannot be properly serviced by these PSAPs. If a caller is using a non-cellular wireless device, such as a WiFi enabled wireless device, an operator at a PSAP with E911 Phase I capabilities is unable to determine address location based on GPS coordinates that are received from the caller. And, because WiFi enabled wireless devices do not communicate via a cellular network, there is no cell site or base station location information to be communicated to the PSAP.